Modification on LSA speech enhancement for speech recognition

Speech recognition performance deteriorates in face of unknown noise. Speech enhancement offers a solution by reducing the noise in speech at runtime. However, it also introduces artificial distortions to the speech signals. In this paper, we aim at reducing the artifacts that has adverse effects on speech recognition. With this motivation, we propose a modification scheme including smoothing adaptation to frame SNR and reestimation of a priori SNR for spectral-domain log-spectral-amplitude (LSA) speech enhancement. The experiments show that the proposed scheme of enhancement significantly improves the performance of the state-of-the-art speech recognition over the baseline speech enhancement.